1. Technical Field
The present invention relates to an image forming apparatus.
2. Related Art
As an apparatus that projects light on a surface of an object such as a screen and displays a desired image on the projection surface of the screen has been known. As the projector, one using a light scanner for one-dimensional or two-dimensional scanning with light has been put into practice (for example, see Patent Document 1 (JP-A-2008-116668)).
The projector described in Patent Document 1 has a first light scanner in which a movable plate having a light reflection part rotates around the x-axis, a second light scanner in which a movable plate having a light reflection part rotates around the y-axis, and a light source unit that outputs light such as a laser. In the projector, scanning is performed with the light output from the light source unit using the first light scanner, scanning is performed with the light used for the scanning using the second light scanner, and thereby, two-dimensional scanning is performed with light and a desired image is displayed on a screen.
In the projector, the shape and size of a drawable region as a region where an image can be displayed (a range in which light scanning can be performed on the display surface) are always constant, and the image is displayed in the region at constant resolution.
Accordingly, in the projector described in Patent Document 1, the area of the region with no image formed of the drawable region may become larger depending on the shape (outer shape) and the size of the image to be displayed. In this case, the ratio of the period for image drawing in one frame (so-called time-aperture ratio) becomes lower. The lower time-aperture ratio means the lower energy efficiency.
Further, in the case where the shape and size of the screen is largely different from the shape and size of the drawable region, the area of the part off-screen of the drawable region becomes larger, or the area of the part not the drawable region of the region on the screen becomes larger. This case is not efficient.